| 摘要 |
PURPOSE:To produce a semiconductor device with the safe operation region of its transistors enlarged by a method wherein diode withstand voltages are controlled by the horizontal distance between a base region and thickly doped region. CONSTITUTION:P is further diffused into a surface of a P-doped N<+> type Si substrate 12 for the formation of a thickly doped collector region 13. Photoetching is performed on an SiO2 film 14 on the other surface of the substrate 12 for the provision of a window, wherethrough B is selectively diffused for the formation of a base region 15 and ring base region 18. After this, another window is provided for an emitter region in the SiO2 film located on the base region 15 and, simultaneously, a third window is provided for a diode cathode region in a portion in contact with an edge of the ring baser region 18. Through this window, P is diffused, for the formation of an N<++> type emitter region 16 and diode cathode region 17. Finally, electrodes 19-21 are built respectively in the collector, base, and emitter regions, for the completion of the power transistor. |
